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Transformer is 75kva so that exception would not apply in this instance right?

The size of the transformer doesnt matter. Generally, the only time one might use this exception is between detached structures. An application where this would be useful is where you have a long wire run where you want to step up voltage to say 480V or 600V. You would ground one of the secondary conductors and bond at both ends, thus you would only need 2 conductors for the wire run.

The size of the transformer doesnt matter. Generally, the only time one might use this exception is between detached structures. An application where this would be useful is where you have a long wire run where you want to step up voltage to say 480V or 600V. You would ground one of the secondary conductors and bond at both ends, thus you would only need 2 conductors for the wire run.

I don't have the code in front of me but when I looked it up it had mentioned about transformer being less then 1000va for exception to be used

I don't have the code in front of me but when I looked it up it had mentioned about transformer being less then 1000va for exception to be used

Here's the exception that roger mentioned:

250.30(A)(1)Exception No. 2: If a building or structure is supplied by a
feeder from an outdoor transformer, a system bonding
jumper at both the source and the first disconnecting means
shall be permitted if doing so does not establish a parallel
path for the grounded conductor. If a grounded conductor
is used in this manner, it shall not be smaller than the size
specified for the system bonding jumper but shall not be
required to be larger than the ungrounded conductor(s).
For the purposes of this exception, connection through the
earth shall not be considered as providing a parallel path.

Are there any present or possible metallic paths between the panel and transformer? If there are or will be you will have multiple neutral current paths.

Roger

Just the 3 inch emt that changes over to Greenfield to carry down the conductors. That would be considered as a path for multiple neutral paths right?. I don't want to drag this out it's just I've never bonded twice, I see no reason ever to do it